[Fungal nail infections - an update. Part 2 - From the causative agent to diagnosis - conventional and molecular

P Nenoff1, G Ginter-Hanselmayer, H-J Tietz

  • 1Haut- und Laborarzt/Allergologie, Andrologie, Labor für medizinische Mikrobiologie, Straße des Friedens 8, 04579, Mölbis, Deutschland. nenoff@mykologie-experten.de

Insights

Trichophyton rubrum is the most common cause of fungal nail infections (onychomycosis) globally. Combining traditional methods with new molecular techniques like PCR improves diagnostic accuracy for nail infections.

Area of Science:

  • Medical Mycology
  • Infectious Diseases

Context:

  • Onychomycosis is a common fungal infection affecting toenails and fingernails.
  • Accurate identification of causative agents is crucial for effective treatment.

Purpose:

  • To review the common fungal pathogens causing onychomycosis.
  • To discuss conventional and molecular diagnostic methods for onychomycosis.

Summary:

  • Trichophyton rubrum and T. interdigitale are the leading dermatophytes causing onychomycosis.
  • Yeasts like Candida spp. and non-dermatophyte molds (NDM) such as Scopulariopsis and Aspergillus are also implicated.
  • Conventional diagnostics (direct microscopy, culture) and molecular methods (PCR) are used, with combined approaches offering higher sensitivity.

Impact:

  • Highlights the spectrum of fungal organisms responsible for onychomycosis.
  • Emphasizes the importance of laboratory diagnosis for identifying specific pathogens.
  • Advocates for the integration of molecular techniques to enhance diagnostic performance in mycology.

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